Laser beams turn Moon into wifi hotspot

Space / 3 June 2014, 10:19am

Kieran Legg

An airplane passes the full moon, known in the Farmers' Almanac as the "Wolf Moon," on its final approach to Los Angeles International Airport over Whittier, Calif. on Wednesday, Jan. 15, 2014. (AP Photo/Nick Ut)

Cape Town - A future of living on the moon might still be a dream, but one thing is certain: the orbiting rock’s next visitors will at least be able to update their Facebook page.

A team of scientists has spent the past year shooting lasers at the moon, and the result? It’s now a wi-fi hot spot.

Details will be revealed this weekend, but the US-based Optical Society has offered a peek at the technology.

This is no ordinary connection. You aren’t going to be dialling in to it from your local coffee shop.

The team, made up of members of Nasa and the Massachusetts Institute of Technology (MIT), made history last year when their Lunar Laser Communication Demonstration transmitted data over the 384 633km that separate Earth and its moon.

At 19.44 megabits per second, it’s not only faster than the best satellite uplink used in the past, it is also much faster than the average internet speed in South Africa.

“Communicating at high data rates from Earth to the moon with laser beams is challenging because of the distance, spreading out the light,” said Mark Stevens, of the MIT Lincoln Laboratory.

“It’s doubly difficult going through the atmosphere because turbulence can bend light, causing rapid fading or dropouts of the signal at the receiver.”

It may be innovative, but it’s not without the kinks and glitches that plague most wireless internet connections. Basic number crunching revealed there would be a three-second delay between the data being sent and received along the laser beam.

The connection was made possible using four separate telescopes at the ground terminal at White Sands, New Mexico. Each telescope is about 15cm in diameter and is fed by a laser transmitter that sends information coded as pulses of infrared light.

Stevens said four telescopes were used to ensure the signal made it to the receiver, which is mounted on a satellite orbiting the moon.

The new method is more than 4 800 times faster than any other, and this weekend the team will unveil its findings publicly.

And in another spacebound quest, London’s Daily Mail reports that search engine giant Google will launch 180 satellites into orbit to provide internet to about 4.8 billion people who do not have access to the web. - Cape Argus